<!DOCTYPE html>
<html lang="en">
<head>
</head>
<script>
    function changeImage() {
        let img = document.getElementsByTagName("img")[0];
        if (img.src === "http://localhost:63342/wsb/%E6%B1%AA%E9%AA%8F20190311/img/off.gif") {
            img.src = "http://localhost:63342/wsb/%E6%B1%AA%E9%AA%8F20190311/img/on.gif"
        } else {
            img.src = "http://localhost:63342/wsb/%E6%B1%AA%E9%AA%8F20190311/img/off.gif"
        }
    }

</script>
<body>
<div class="box">
    <img src="../img/off.gif" onclick="changeImage()">
</div>
</body>
</html>